A method for unloading fluids from an oil and gas well, pipeline or flowline includes using a synergistic combination of an alkyl glucoside and an amphoteric surfactant as a foaming composition. In an illustrative embodiment, a document object model tree is processed to identify custom tags. The seat can swivel or be fixed by an anti-rotation means. The AD conversion circuit 400 sets its AD conversion range based on this maximum voltage value Vmax2, and sequentially AD-converts the signal voltages Vn2. A determination of whether the data fragment is located in the data fragment cache is made.